To provide the necessary ventilation for the operator's cab of a material handling implement such as a tractor or the like, the one or more doors of the cab are typically provided with sliding or hingedly mounted glass window panels. While such arrangements are very commonly employed, the provision of such openable windows entails several distinct disadvantages. Because of the relatively greater number of components required in comparison to a door structure without movable windows, design and manufacture expenses are invariably relatively greater. The resultant door structure is also relatively heavy. Because the movable window panels must be easily operable, assembly and adjustment of the door are also complicated.
Accordingly, it is desirable to provide an arrangement for effecting ventilation of the cab of a material handling implement without resort to use of movable windows in the cab door. It is particularly desirable for such an arrangement to be straightforward in construction for economical manufacture and ease in service and repair, while at the same time being convenient to operate and capable of providing adequate ventilation for the comfort of the operator.